Outgoing links from your website have as important effect as incoming links and it is important to your online success. These effects can be summarised as follows:
Outgoing links affect your website search engines ranking.
The quality of the outgoing link from your website effect your website ranking, for example if you link to a spam website then search engine think that your site is a spam site also and panelize it or even ban it. Another example is link farms, if search engine see that you site have links to link farms then your site also harmed by these links. That means you must make sure that all the outgoing links from your website must be quality links.
Outgoing links affect your website visitors.
Outgoing links value your site in the eyes of your visitors; if you link to a high quality websites then your visitors appreciate your help by giving them quality information. So let say you site can be trusted as a good source of useful information. On the other hand bad links can show your website as not professional and you look like hiding info from your visitors that make them go away from your site.
You are not losing visitors by outgoing links but you are getting more traffic.
Your visitors will leave your website sooner or later, they will not stay forever, so instead of letting them go back to the search engine to look for other resources, you can give them quality links which they appreciate it, and make them come back again and again.
Conclusion is if you carefully choose your outgoing links you can improve the quality of your website and improve your traffic also